Mold to be used in the manufacture of concrete ceilings



FIG. 1 is a bottom plan view of the inner surface of a mold to be used in the manufacture of concrete ceilings showing my new design;

FIG. 2 is a sectional view taken in the direction of the arrows on line 2--2 of FIG. 1. 

The ornamental design for a mold to be used in the manufacture of concrete ceilings, as shown. 